// Copyright 2022 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef COMPONENTS_UKM_UKM_RECORDER_OBSERVER_H_
#define COMPONENTS_UKM_UKM_RECORDER_OBSERVER_H_

#include <vector>

#include "base/observer_list_types.h"
#include "components/ukm/ukm_consent_state.h"
#include "services/metrics/public/cpp/ukm_source_id.h"
#include "services/metrics/public/mojom/ukm_interface.mojom.h"
#include "url/gurl.h"

namespace ukm {

// Base class for observing UkmRecorderImpl. This object is notified when
// a new UKM entry is added, or when a source URL is updated, or when
// entries are purged. Observers are notified even if |recording_enabled_| is
// false. All the methods are notified on the same SequencedTaskRunner
// on which the observer is added.
class COMPONENT_EXPORT(UKM_RECORDER) UkmRecorderObserver
    : public base::CheckedObserver {
 public:
  UkmRecorderObserver() = default;
  ~UkmRecorderObserver() override = default;
  UkmRecorderObserver(const UkmRecorderObserver&) = delete;
  UkmRecorderObserver& operator=(const UkmRecorderObserver&) = delete;

  // Called when a new UKM entry is added.
  virtual void OnEntryAdded(mojom::UkmEntryPtr entry);

  // Called when URLs are updated for a |source_id|.
  virtual void OnUpdateSourceURL(SourceId source_id,
                                 const std::vector<GURL>& urls);

  // Called when UKM entries related to the given URL scheme should be purged.
  virtual void OnPurgeRecordingsWithUrlScheme(const std::string& url_scheme);

  // Called when all UKM entries should be purged.
  virtual void OnPurge();

  // Legacy method. Called when the UKM consent state is changed in any way, for
  // the new state to take effect. |state| is the collection of accepted consent
  // types. Each consent type is true iff the client has granted this consent on
  // all their Chrome profiles and URL-keyed anonymized data collection is
  // enabled for all profiles.
  // Note: This method is active when the metrics consent restructure feature
  // flag is disabled. Once the feature is enabled, this method will no longer
  // be called and `OnUkmAllowedStateChanged(bool ukm_allowed)` will be used
  // instead. While the feature flag is in transition, both methods must be
  // implemented.
  virtual void OnUkmAllowedStateChanged(UkmConsentState state);

  // New method. Called when UKM allowed state changes. |ukm_allowed| is true if
  // UKM is allowed on all profiles. Note: This method is currently behind the
  // metrics consent restructure feature flag. Once the feature is enabled, this
  // will be the only method called to notify observers of UKM allowed state
  // changes. During the transition, both methods must be implemented.
  virtual void OnUkmAllowedStateChanged(bool ukm_allowed);
};

}  // namespace ukm

#endif  // COMPONENTS_UKM_UKM_RECORDER_OBSERVER_H_